Getting into Field Target Shooting Part 5

The need to accurately estimate the range to a target is a basic requirement for any hunter or FT shooter. With one exception, it is a skill that needs to be practiced and constantly evaluated if consistent results are to be achieved. This applies to the three most common methods we use today and does not include the use of laser rangefinders. These devices are very accurate, work exceptionally well in most conditions, and can be operated pretty accurately by a well trained monkey in no time at all.

They are a useful tool out in the field when time allows and I own one myself; a Leica LRF 900. It performs faultlessly and is a useful addition to my kit. However, they are not allowed in competition and so other methods have to be employed! Apart from the basic way of looking at an object and ‘guestimating’ its range by eye, there are other and better methods. These involve the use of the telescopic sight, and at the distances we are talking about, they are more accurate than eyeballing the target!

Bracketing

One of these has become known as ‘bracketing’ and can be applied successfully with any scope that uses a reticle with more than one usable aiming point. Even a standard Duplex /30-30 being just one example. For a given size of target there will be a relationship between it and two given points on the pattern!

This is particularly good news for hunters with lower power scopes and legal 12ft/lb air rifles, as the sensible limit for any game would be 40yds and gives this system every chance of working well within these constraints. More info later.

Another method that has become very popular over the last 10 years, as a direct result of FT shooting, is ‘parallaxing’. I use the term loosely, as its meaning has little to do with range finding, in fact when you read the handbooks that accompany these scopes; as far as the manufacturers are concerned the parallax is something you set after you decide the range.

Nevertheless, the way it has been adapted for the job has become a very useful and generally accurate method.

Practice and skill!

I say generally, as despite what you might hear about all these ‘super scopes’ and their ability to read ranges to within inches at 55yds, it takes practice and skill to use one correctly. That degree of accuracy I have yet to see, although it is getting closer by the season, as manufacturers continue to build scopes with this method in mind.

At this moment in time, a skilled competitor can range within a couple of feet within a 165ft (55yd) window. The method relies on high magnification to provide a shallow depth of field and the shooter basically adjusts the focus for the clearest sight picture at a given distance. These are then marked on the focus wheel from 10 to 55 or 60yds, usually every yard from 10 to around 25yds and then every 2.5yds out to maximum. The factory-set marks are there only as a guide and can be different for each person, depending on the set position of the ocular bell.

This is the first thing that needs to be set on a scope and entails focus adjustment, so that the reticle appears sharp when viewed in the aiming position. Change this and the focus point will also change, altering the position of the main focus adjustment! However, for those with low power scopes, and I am including anything up to 16x magnification, using the focus method at ranges above 30yds will be inconsistent and even worse with lowerpowered optics.

Military 100M

For those users, it comes down to using the bracketing method, or simply making a ‘guesstimate’ with the eye. When doing this, you might consider using a scaleddown version of the military ‘100-meter method’. For our airgun purposes, we will call it the ‘10 meter method’. In fact, I’m old school, so we will call it the ’10 yard method’!

You fix into your mind, a vision of how far 10 yards extends in front of you. You then work your way out in multiples of 10 to the target. This can work reasonably well, depending on the terrain you have to deal with. The problem is that the human eye can be easily fooled by the landscape and these are just a few of the problems we have to deal with.

1) Ground that slopes up away from you gives the illusion of greater distance and conversely, the reverse tends to shorten it

2) Ranging over terrain that is irregular will lead to over-estimation of distance, as the eye follows all the irregularities between it and the target. The opposite will apply when ranging over flat, smooth surfaces

3) A target that stands out against its background will appear to be closer than it really is, as it will if the sun shines directly onto it from behind the shooter

4) Targets in a narrow avenue of bushes or trees will appear further away than they really are, particularly if they are adjacent to an object much bigger than they are. There are many more examples but I guess you get the idea by now.

Working average

Ranging by eye alone is a risky business when we are talking more or less single yards. We need to be within a couple of yards at our maximum ranges with a 12ft/ lb air rifle. An effective way of determining range when shooting targets of a known size is ‘bracketing’.

This term has been in use in military circles for a long time and although used to describe a ranging technique, it is a different system.

They take the longest and shortest estimate of a targets range, the bracket, and use the average as the true figure. This should increase with target distance. Bracketing to the FT shooter means using the relationship between their reticle and the target to estimate a particular range.

This is not a new method and has been used to good effect for many years by both hunter and soldier alike. It is a reasonably good way of estimating range when the target is of a known size and preferably motionless. The reticle also has an inverse relationship to the target. This means that if, for example, a target fills the reticle tip to tip at 25yds, it will appear half the size at double the distance (pictures 2 and 2a). This opens up numerous permutations when viewing the target and adds more information to our range chart.

This method also works in failing light, when all else is pure guesswork.

Pattern potential

There are many types of reticle available, which can be used specifically to range-find and although they may be for different size targets than we envisage shooting at, they will still work efficiently on any size, once the relationship between target and reticle has been established.

Another method, is to actually turn the power zoom ring in or out while viewing the target, applying the same sight picture to each one but with the zoom ring marked off for the different ranges. This system will work well with scopes that have their reticles in what is termed the second focal plane (SFP). This means that the reticle remains at a constant size as the power ring is turned but the target size changes in relationship to it. This system can be used to find the perfect ‘bracket’; then simply read off the range on the power ring.

If you own a scope with the reticle in the first focal plane (FFP), the target and the reticle will stay in scale with each other as the magnification is changed and the relationship between them will remain constant.

Most manufacturers now offer custom reticles that provide numerous reference points that can be used for bracketing and it is a reliable way of estimating range with a lower-power scope!

Acceptable performance

With practice, acceptable rang-finding is possible with a couple of the techniques described above, sometimes using a combination of them to find the distance. Indeed, in the hunter version of FT, HFT, the scope cannot be adjusted during the course of fire and the power is limited to 12x magnification. This leaves bracketing as the only practical method of range-finding.

By far the best method has to be the ‘parallax’ or ‘focus’ system if time and rules allow. It is the one most extensively used in FT and gets the shooter within feet of the actual range, if their technique is right. Good enough for a hit every time! Like all else in target shooting, it requires some knowledge, familiarity, and practice to get it right.

The next thing to work on is probably the most neglected aspect in FT; the shooter themselves! So much improvement can be gained by applying the basic rules of marksmanship and this is what we will examine next month.

Happy shooting!